{"cve":"CVE-2026-42486","nvd":{"published":"2026-07-09T16:16:41.443","modified":"2026-10-25T17:10:00.197","status":"Deferred","description":"[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]\nXAPI can configure different users with different roles, using Role\nBased Access Control.  For more details, see:\n\n  https://docs.xenserver.com/en-us/xencenter/current-release/rbac-overview.html#rbac-roles\n\nThe pool-admin role is fully privileged.  Notably, users with this role\ncan also SSH into the host as root.\n\nThe other administrator roles are pool-operator, vm-power-admin and\nvm-admin, each of which are authorised to configure and manage various\naspects of the system.\n\nSome settings are inadequately restricted, and can be set by a lower\nprivilege of administrator than expected.\n\n * CVE-2026-23559: A vm-admin can set VBD.other_config:backend-local and\n   turn arbitrary files in dom0 into VDIs (virtual disks) and give said\n   disks to a VM they control.  This is an arbitrary read and/or modify\n   of files in dom0.\n\n * CVE-2026-23560: A vm-admin can set VM.other-config:is_system_domain\n   and mark a VM as a system domain.  System domains are ignored and\n   left running during certain other host/pool operations, and may be\n   hidden from view in tooling.\n\n * CVE-2026-23561: A vm-admin can set VM.other_config:storage_driver_domain\n   and mark a VM as the storage domain for a particular host storage\n   connection (PBD). Shutting down the VM can cause the PBD to be\n   erroneously marked as unplugged when it is not.\n\n * CVE-2026-23562: Configuration of PCI passthrough is normally\n   restricted to the pool-admin role.  However one API was missing this\n   check, allowing a vm-admin access to unintended host hardware.\n\n * CVE-2026-42486: A vm-admin can set the VM.platform:hvm_serial\n   parameter, which should be restricted to the pool-admin role, as it\n   can allow arbitrary dom0 file write.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H","score":9.4},"cvss_v3":null,"cwes":["CWE-250"],"references":["https://xenbits.xen.org/xsa/advisory-489.html"],"products":[],"source":"nvd","synced_at":"2026-10-25T17:50:06.907763985+00:00"},"epss":{"cve":"CVE-2026-42486","score":0.00167,"percentile":0.05911,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}